PHOTOLUMINESCENCE STUDIES ON VERY HIGH-DENSITY 2-DIMENSIONAL ELECTRON GASES IN PSEUDOMORPHIC MODULATION-DOPED QUANTUM-WELLS

We present photoluminescence studies on highly dense two-dimensional electron gases in selectively Si delta-doped GaAs/In0.18Ga0.82As/Al0.25Ga0.75As quantum wells (N(s) = 4.24 x 10(12) cm-2). Five well-resolved photoluminescence lines centered at 1.4194, 1.4506, 1.4609, 1.4695 and 1.4808 eV were observed, which are attributed to the subband excition emission. The subband separations clearly exhibit the feature of a typical quantum well with triangle and square potential. These very intensive and sharp luminescence peaks with linewidths of 2.2 to 3.5 meV indicate the high quality of the structures. Their dependence on the excitation intensity and temperatures are also discussed.

A voltage-controlled ring oscillator using InP full enhancement-mode HEMT logic

A voltage-controlled ring oscillator (VCO) based on a full enhancement-mode InAIAs/InGaAs/InP high electron mobility transistor (HEMT) logic is proposed. An enhancement-mode HEMT (E-HEMT) is fabricated, whose threshold is demonstrated to be 10 mV. The model of the E-HEMT is established and used in the SPICE simulation of the VCO. The result proves that the full E-HEMT logic technology can be applied to the VCO. And compared with the HEMT DCFL technology, the complexity of our fabrication process is reduced and the reliability is improved.

分子束外延生长赝配高电子迁移率超高速微结构功能材料里深中心识别

应用深能级瞬态谱（DLTS）技术研究分子束外延（MBE）生长的high electron mobility transistors （HEMT）和Pseudomorphic high electron mobility transistors （P-HEMT）结构深中心行为。样品的DLTS谱表明，在HEMT和P-HEMT结构的n-AlGaAs层里存在着较大浓度（10~(15)-10~(17)cm~(-3)）和俘获截面（10~(-16)cm~2）的近禁带中部电子争阱。它们可能与AlGaAs层的氧含量有关。同时还观察到P-HEMT结构晶格不匹配的AlGaAs/InGaAs/GaAs系统在AlGaAs里产生的应力引起DX中心（与硅有关）能级位置的有序移动。其移动量可作为应力大小的一个判据，表明DLTS技术是定性识别此应力的可靠和简便的工具。

High-quality metamorphic HEMT grown on GaAs substrates by MBE

Metamorphic high electron mobility transistor (M-HEMT) structures have been grown on GaAs substrates by molecular beam epitaxy (MBE). Linearly graded and the step-graded InGaAs and InAlAs buffet layers hal e been compared, and TEM, PL and low-temperature Hall have been used to analyze the properties of the buffer layers and the M-HEMT structure. For a single-delta-doped M-HEMT structure with an In0.53Ga0.47As channel layer and a 0.8 mum step-graded InAlAs buffer layer, room-temperature mobility of 9000 cm(2)/V s and a sheet electron density as high as 3.6 x 10(12)/cm(2) are obtained. These results are nearly equivalent to those obtained for the same structure grown on an InP substrate. A basic M-HEMT device with 1 mum gate was fabricated, and g(m) is larger than 400 mS/mm. (C) 2001 Elsevier Science B.V. All rights reserved.

1.55-mu m InGaAs/InGaAlAs MQW vertical-cavity surface-emitting lasers with InGaAlAs/InP distributed Bragg reflectors

High-performance InGaAs/InGaAlAs multiple-quantum-well vertical-cavity surface-emitting lasers (VCSELs) with lnGaAlAs/InP distributed Bragg reflectors are proposed for operation at the wavelength of 1.55 mum. The lasers have good heat diffusion characteristic, large index contrast in DBRs, and weak temperature sensitivity. They could be fabricated either by metal-organic chemical vapor deposition (MOCVD) or by molecular beam epitaxy (MBE) growth. The laser light-current characteristics indicate that a suitable reflectivity of the DBR on the light output side in a laser makes its output power increase greatly and its lasing threshold current reduce significantly, and that a small VCSEL could output the power around its maximum for the output mirror at the reflectivity varying in a broader range than a large VCSEL does. (C) 2004 Elsevier Ltd. All rights reserved.

InGaAs/InP系材料的MCVPE生长及特性研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

正面进光InGaAs/InP SAGM APD器件的研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

AlGaAs/GaAs,InGaAs/GaAs体系光电子材料的MBE生长及相关性质研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

高质量InGaAs/AlGaAs应变量子阱激光器的研制

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

HEMT材料界面特性及其器件的二维数值模拟

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

GaAs,InGaAs垂直腔面发射激光器的研究及理论分析

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

InGaAs/GaAs名变量子阱光学性质的研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

InGaAs低阈值垂直腔面发射激光器的研制

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

GaAs,InGaAs量子线分子束外延生长和光学性质研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z

应变异质结构(InGaAs/Al)GaAs材料的分子束外延生长.性质及其相关器件的研究

Submitted by zhangdi (zhangdi@red.semi.ac.cn) on 2009-04-13T11:45:31Z